Anthony Elding's last-gasp leveller grabbed Grimsby a point at 10-man Kidderminster.
It started well for the hosts when Nick Wright slotted home from close range.
Marc Williams and Jack Byrne almost added a second as Harriers dominated until Kyle Storer's foul on Serge Makofo earnt him a second yellow card.
That brought Grimsby back into the match and Elding latched onto Lee Ridley's left-wing cross to fire high into the net to salvage them a point.
VIEWS FROM THE DRESSING ROOM
Harriers manager Steve Burr told BBC Hereford and Worcester:
"The overall performance was good, I thought we were a constant threat going forward.
"To lose a goal in injury time was a big blow to us. I really feel for the lads as they have done very well.
"We had plenty of chances in the first half to have killed it off, but sometimes you don't get what you want."